Method of heating and evaporating liquids.



0. K. zwmemmmem. METHOD 0? HEATING AND EVAPORATING LIQUIDB. APPLICATIONFILED NOV. 26, 1911. 1 1Q4 285 Pat entad July 2.3, 1934.

2 BHEBTE-SHBE'I' l.

mmkms;

0. K. ZWINGENBERGER. Z-ZETHOD 0F HEATING AND EVAPORATING LIQUIDS.

APPLICATION FILED NOV. 25,1911,

?atented July 21, 1914,

2 SHEETS-SHEET 2.

WI TN E 885 8:

IlNlTED STATEd PAEENT @l l lQiE.

OTTO K. ZWINGENBERGER, OF PERTH AMBOY, NEW ERSEY, ASSIGNOB TO THEBOESSLER 8r, HASSLAGHER CHEMICAL 00., OF NEW YORK, N. Y A CORPORA- """N'OF N'Elff YORK.

Specification of Letters Patent.

Patented .nu 2i, 191a. i

Applicationfiled November 25, 1911. Serial No. 662,278.

T 0 all whom it may concern.

Be it known that I, O'r'ro K. ZWINGEN- nicuona, a subject of the Emperorof Germany, and a resident of Perth Amboy, in the county of Middlescxand State of New Jersey, have invented certain new and use tulImprovements in the Method of Heating and llvaporating Liquids, of whichthe following is a specification.

The invention relates to the systematic utilization of the sensible heatof producer gas and other like gases for the purpose of heating andevaporating liquids, concentrating chemical solutions and the like. Inconcentrating chemical solutions by the heat from exhaust-steam, torexample,there were at the outset, certain difficulties which, however,did not originate so much with regard to the application of steam forthis purpose as in the action of the chemicals on the matcrial oi"? theevaporation apparatus. These latter ditliculties, as well as theconstruction of suitable vacuum evaporating apparatus, which also aidedin overcoming them, were easily solved in a relatively short time.

The use of gas engines as a source of power, however, gives to thequestion of uti-f lizing the waste heat of this modern machiner; quiteanother aspect. as we have here two dilierent sources of waste heat.units of such engines are ted with so-called producer gas, which isgenerated in producers close to the engine station. These producer gasesrepresent one source of wast heat as they must be cooled before use inthe engine, the other source being the hot gas produced by theexplosions in the cylinder of the engine. The utilization of thesensible heat of such producer gas, of the explosion gases ofgasengincsof coke ovengas and the like gases for mating and evapcrating"liquids is the purpose of this invention. The term liquids as usedherein is intended to cover broadly any aqueous solution containing achemical compound or a mixture of such compounds. The utilization of theheat from hot producer gases for the pu l-pose of evaporating suchliquids rects with many tlifiicultics having their chief source in thegreat difference between the temperature of the applied gases and theboiling point of the liquids to be evaporated. For example liquids,carrying dissol ved salts, alkalis or other chemicals of usually solidLarge.

consistency, cannot be evaporated with the expected good results whenworking according to the usual methods recommended by success in otherlines. Certain phenomena. occur due to the high temperature of thegasesand to the nature of the chemicals d-islgases, over aplurality ofprimary evaporation vessels 1n such a way that the liquid 1n quest1onWlll never reach the boiling point, but may always be kept, on theaverage, about 5 degrees Centigrade below the boiling point, thusreducing the effect of the heat of the gases to such an extent thatlater .on the evaporating of liquids may be performed in the same way asis done by steam in the various apparatus according to the usualpractice in this line of work.

I am aware that coke-oven gases for in: stance, have been used forconcentrating liquids, but this was regularly done in plain pans withoutany regulation of the distribution of gas in the sense of my inventionand consequently there was no control of the temperature in the sense ofmy invention to a keep the liquid constantly somewhat below the boilingpoint.

I will now describe my process in connection with an apparatusillustrating one means of practising my process and for a full and clearunderstanding thereof, refer ence is made to the accompanying drawingsin which Figure 1 is a front elevation, partly in section and partlybroken away. of a por, tion of the apparatus, and Fig. 2 is a plan view,partlybroken away, of-the complete.

apparatus. .105

Similar letters and numerals of ream ence indicate similar partsthroughout the several views.

or 1,1 as

The hot producer gases coming from a producer (not shown) through a nacin teed plpe A are conducted through pipe 1 controlled by valve E, ofany su1table construe tlon into a primary evaporation vessel C wherethey enter a flue G whence they are conducted through a system ofparallel tubes B arranged as 1n a horizontal tubular boiler the hotroducer gases enterin 7 m at the bottom and being caused to pass throughthe respective layers of pipes B b means of baflielates B arran ed 1nthe CD fiues C The'gases leave the tubes B near the top of vessel C; andenter main collector pipe D. Any suitable number of vessels C may bearranged in parallel and provided w h the connection described, in Fig,2, for example I have shown four such vessels.

By admitting the hot producer gases into the tubes B at the'bottom orvessel (3 the liquid in the vessel C surrounding the tubes l3 issoheated that it undergoes a. steady circulation from the bottom to thetop ot the vessel as the liquid in the lower part is subjected to agreater heat than that in the upper part of the vessel and hencebecoming lighter, rises and causes a continuous circulation which makesfor a uniform tern-- perature of the liquid in said vessel.

All of the main-pipes, connection pipes and valves which are subjectedto the heat from the hot'gases are preferably lined in-v side withsuitable heat insulating material (not shown); a v

Main'collector pipe D may be diseonnect-- ed from any of-vessels C byany of the well known Ways, such asby a controlling valve in pipe K (notshown).

. The hot gases, after passing through tubes B and vessel C, enter themain pipe I) through pipe K, pipe D acting as a colleetor pipe from theseveral vessels C, and from there the gases pass into asystem of maintubular boilers- F F, the construction of which is more specificallypointed out hereinafter and which is clearly illustratedi 'in thedrawings. There may be any suitable number of main steam boilersconnected either in series, in parallel or series parallel, but I havehere shown two boilers connected in series as I believe such an.arrangement to be the most efficient, Each of boilers F F is preferablyconnected with a series of auxiliary boilers, here shown conslstlng oftwo such auxiliary boilers in each series,O and O and Panel P respcctively. The auxiliary boilers in their operationpreferably depend onthe steam ,Which is generated in the boilers F and l by the hot gaspassing through these latter; theauxiliary boilers beinr preferably. op-

erated on the same princip e the v'aoui'un-i evaporation apparatus usedin the various industmeaas for mstan'ce, in the raanulfao ture of sugarand soda wherein considerable volumes of liquids are evaporated. In theapparatus shown the steam generated in boiler l?- servs' to heat boiler0 and the steam enerated in boiler er 0 The boilers P and are heated be]by the steam from boiler F in a correspond ing manner: Pipe 0 conductsthe steam from lmiler F to near the bottom of boiler O and pipe O"conducts the steam from boiler 0 to near the bottom oi boiler 0 servesto heat mounted on an elevation above the of the apparatus and providedwith suitable discharge connections G and G, G dis ch :2 rging into theseries of boilers P, P and F and Cr discharging tl'rrough pipe G intothe series of boilers U and F Under general conditions this courseguarantees the best utilization of the heat. W hen the liquid fromboiler F has reached the proper concei'itration or whenever it may beotherwise desirable, the liquid is trziinstc red from boiler if toboiler l through. pipe G by .iueans of pump (not shown) or any othersuitable means. I

all the boilers, but especlally in boilers F and the liquid should enterat the bottom and leave at the top. From boiler F the liquid may bedelivered if desired, by a suitable pump (not shown), through pipe Ginto main liquor pipe G from which subconnectimi pipes G lead to any ofthe.

vessels G so that the preheated and. concen trated liquids may bedistributed into the vessels (1 Pipe s1 is in direct connection with thewreak-liquor storage taul; l y so that either cold or preheated,dilutevor concentrated liquids may be supplied to vessels C as thesituation may'require. Though the conduction of liquids in the courserescribed above is generally preferred, it is to be understood that inthe conduction of the liquid many Vzulfli'lORS may take place and thatit may also be arranged that liquids of dif ent liinds may be treatedsiinultaneously in the various parts of the apparatus.

The passage oi the through the tubular rollers ll, usual way, the gasesentering the boilers in the upprr part the fines and leaving at thebottom, but the producer gases have alreadytransferred considerable partof their heat to the liquid in the vessel C the h may be eiifected inthe get as much possible of the avail-' able h at loo i therefore,prefer to provide r With-partitions il and low the upper wall of theflue, thus divid ingthe line space-into two equal compart ments and tocause the hot gases to enter the boiler F near the bottom through pipe Kpass over partition H leave boiler -E through pipe K and pass in thesame zig-zag way through boiler F and thence through the other mainsteam boilers which may be arranged in the series, until the gases areso cooled down that the heat they are a lead off-the water vapor and toconstruct the hoods so that the exit thereto may be osed by a suitabledamper as shown in Fig. 1, and so that air may; enter the vessels .Cthrough a series of inlets L in such manner as to strike the surface ofthe liquid and to thus increase the vaporization in a very favorablemanner. The air highly saturated with water vapor leaves throughthe exitM into a pipe N and may then be blown 1) suitable means (not shown) intothe m stion zone of the gas producer to supply the air for thecombustion and the Water for the generation of hydrogen and carbonmonoxid.

By distributing the hot gases over a pluralityof vessels 0 I am able tobring as much heating surface, which might more properly be calledcooling surface, into action as I deem necessary with the purpose inview, as I am thus able to admit to each of the vessehs C just as muchheat in the form of hot gases as may be necessary in order to attain thetemperature at which 'I wish to keep the liquid and as hereinabovepoint-- ed out, by admitting the hot gas to the tubes B at the lowestpart of the vessels 0, I create a steady circulation of the liquid sothat a uniform temperature is caused to prevail in the vessels C. It isreadily seen that by this method no conditions for steam generatingarise around the tubes B and, although it seems contrary to the purposeof evaporating liquids, this is one of the points upon which the successof the work depends. If hot gases are admitted to the tubes B insuchquantities that steam generation sets in, the chemicals dissolved inthe liquid would take part in the process by covering the tubes with anever increasing coat of solid material, an effect which is explained bythe Leidenfrost phenomenon, and thus vaporization will become impossiblein a very short time and great inconvenience be caused b the-delay andlabor entailed by the inju icious exposure of the liquids to the hotproducer gases, explosion gases, coke-oven gases or other gases whichmight be As in my process I-eausea steady circulation and avoid thegeneration. of steam around the tubes B, the Leidentrost phenomenoncannot occur and all the steady circulation is going on in the vessel C,

the liquid on top is very nearly as hot as that at'the bottom. By mymethod the vaporiuation is going on only at the surface of the liquid. N

Crystals may segregate from the liquid when the latter becomessaturated-in the course of the process, but these crystals are not sobad in their effect because they are loose and settle as sediment at thebottom of the vessels, whence they may be removed through outlets CValves C permit liquids to be drawn from vessels (1. Should the crystalsoccur in too great masses the liquid may be stirred in any of the wellknown ways.

I By dividing the fines of boilers F and F into two compartments by apartition, the gases are caused to travel in a path which is twice aslong as the path they would travel if admitted to the fines of eachboiler at the highest point and drawn ofi at the bottom to enter thefines of th'en'ext boiler again at the highest point. By thisarrangement the number of the required boilers is greatly reduced, forby this system the sensible heat of the gases'is trans ferred to theliquid in the most ettective way, as on account of the buoyancy, the hotgases tend to remain at the higher points around the top of thepartition and move down gradually as they are cooled.

One of the advantages of my method c0nsists in the uniform vaporizationin vessels 0 exclusively from the surface of the li uid; Thoughtheliquid is not kept at the boi ing point and though the effect. maynot be quite as great as it mightbe if theliquid were kept boilingpermanently, all the troubles from incrustations on the heating tubesare avoided, a great deal of inconvenience and labor is saved, and thusthe effect, in the long run, is quite as satisfactory.

Another benefit derived from the process. carried on in vessels C,according to my method,.consists in the fact that the vessels C serve tocontrol or curb down the unfavorable temperatureof the hot gases in muchthe same way theta rheostat controls an electric current, the gasesbeing controllable to such a degree that the amount of heat they carryin passing through vessels C is such as to allow the concentration ofthe liquids in boilers F F 2 to be managed in about the same way as isdone with steam with or without the employment of vacuum. The finalconcentration of liquids, may take place in vessels C, in boilers F orin any other convenient manner.

It is of course understood that various ithruug'la El, rerim' ml?nl'imiges the 1 ranggrnent of part, out epm'ljii nun-i any -z lion asiluscrihe (lelineil in il'lB a; i

claim as new 1 ll rlrsviri: iii lz'rtunt is;

1. fl. method if? l liquiils which mil-l llmrnp li i mlorii in 131""ressrlsa (li'ilillllll'lll ll surh QYflPFViHl'lfli} I prevent thernnl'niz the boiling poifi 1 temperature (if mi: passing the same lhrmQ'LUGHiil'Ug slemn in. axial strain for crap? suitable "Way,

2. A. mcl'li lrl of l llq'iilClS through system vessels, mgulati initialto snicl r" :21 r to prhviirir lv'l from washing, the hi tiallyrtlucingr lhe re: :mil subsequently n :1 series ml boilers, gem boil andusing; sairl Sil. purposes in any suitable vi 4 F3. 51 method {iflimiting liquids which mnraisl's 3 l'hrmigh 5511s 0i 0., vesselsregulating the mhriilledm rsnirl ri i. at the bottom ml smcl r'vaporanonVi ilistrihubi 15;, same {is new the am; over as many 01 'y' in prurent511m and guhseij umii'ly through a series- 1f mile a in said boilers21ml n." :"erlnl slim map-3r an purposes in any Rllllfllf li? l. Amethod cl. l" in,2r :inf evuporir" lii' uii'le; 'lvhinh ron '05 r, X

prm'iary ex i vowels, regulating the qmmliiiy of the rulinitfeil to willre solse hirculaixirig t in a sci i arla tin-(nigh Sfilkll s lrilmfingthe offer as many uvh erar oratioir vessels as neceaszrrv we've-r113 thecentained liquids from rm i-erlmilirig paint, snhsta nrially ri riluriharm periiture of's aiil gas; 51ml. snh wily mars ing the sums; througha series of hoilum generating steam in swirl mailers and m Paid slzemnfor e aparal'inn pnrpiwsw in my suitnb a way" A. methfirl of lrmfiq; andwis'iporriti" liquids which consists in priming Trim;

"less or? prinmry evaporation res g a circula'ialsn of the liquid fromh; he top of the vessels, regulatrlie flilill'li;lil} of "(he admittedto said iliairi miingz; the aver as many pin-5r imi is necessar'v to c51 0 (011* "lined lifiuids from reac ling poin substantiallyrerlucingtlie (if riirl and subsequently came through TL series ofmailers, steam in said mailers and using fr'llillll'l for erapomiionpurpcses in any ble Way. 1

ll. metlmol of hearing zimlevaporating cansists in pissing hot gas a ofprimary evaporation vesring earl: of said vessels re- 1 asnlas'frmlially' uniform temzregulziting the rguantity of the g ss-saigfl vessels, cliiitrihuting the gas many 51ml evzm r=rl;i n vesselsas is thehoiliiig point, substanlemperature of said 'gas y par-King thesame through steam in said for evra porw n ay.

lllS which cnnsists passing hot gas vesse ii, air over the surface ofthe liquiitl in said vessels to increase eyaporw rim, distributing thegas overfl ais inany 0mphrzrrimi re sols as nrzwssary .fbjip re yentfilm remained liquiils from renc flg; the

11mpernliure of said gas and subsequently up up; the smile through aseries of tubw lllClllQ ll; mperature of said gas, subsequently p: ""hlgthis same through ii system hf tuhulmi ho'ilers in m zigzag pzith,generating steam in said boilers mid using said an mi for evnporalzii'igpurposes inmiy suit- 1l)l0 way. D

.l. [K metliml of heating and evaporating liqi'riils which onsi stsjnpassing hill gas through primary iiv aporation vessls; clis i'rilmiingl'lm gas over as many evaporatiom v0 W'lS PU necessary to "prevent thecontained liqimls from reaching the boiling point, snhminimally redrcmgthe tom-murmur of said;

revent iiha contained liquids nod 01 ligating and evaporating h series.01 prinmry evaporation billing point substantially rcrlufirig the! '0 mprevent (he remained liquiclsfrom hing the boiling point, substnntmllyre-fgas and subsequently passing the same through a series of tubularboilers, attenu-. ating the atmosphe *ic pressure in the evaporationchambers of said tubular boilers, generating steam in said boilers andusing said steam for evaporation purposes in any-suitable way.

10. A method of heating and evaporating liquids which consists inpassing hot gas through a system of primary evaporation vessels,distributing the gas over as many such evaporation vessels as isnecessary to prevent the contained liquids from reaching the boilingpoint, substantially reducing the temperature of said gas, subsequentlypassing the same through a system of tubular boilers in a'zig-zag path,generating steam in said boilers and using said steam for evaporationpurposes in any suitable Way.

11. A method of heating and evaporating liquids which consists inpassing hot gas through a system of primary evaporation vessels,distributing the gas over as manyv such evaporation vessels as isnecessary to prevent the contained liquids from reaching the boilingpoint, substantially reducing the through a system of primaryevaporation vessels, distributing the gas over as many such evaporationvessels as is necessary to.

prevent the contained liquids from reaching the boiling point,substantially reducing the temperature of said gas, subsequently passingthe same through a system of main boilers, evaporating liquid andgenerating steam iii-said boilers and passing said steam through aseries of auxiliary boilers containing liquid to be evaporated.

13. A method of heating and evaporating liquids which consists inpassing hot gas through a system of primary evaporation vessels,distributing the gas over as many such evaporation vessels as isnecessary to prevent the contained liquids from reaching the boilirigpoint, substantially reducing the temperature of said gas,subsequentlypassing the "same through ,a system of main boilersevaporating liquid and generating steam in" said boilers, passing saidsteam through a series of auxiliary boilers and attenuating theatmospheric pressure over the liquid in said auxiliary boilers.

14:- A method of heating and evaporating liquids which consists inpassing, hot gas through. a system of primary evaporation vessels,distributing the gas over as many "such evaporation vessels as is,necessary to prevent the contained liquids from reaching the boilingpoint,'subsequently passing said gas through a system of main boilers,generating steam in said boilers, passing said steam through a series ofauxiliary boilers and preheating the liquids to be evaporated by passingthe same successively through the auxiliary boilers and main boilers tothe primary evaporation vessels in a course 0pposite to the co'urse ofthe hot gases and steam in the main boilers and the course of the steamin said auxiliary boilers respectively.

In testimony whereof I have signed this specification in the presence oftwo subscribing witnesses.

OTTO K. ZWXNGENBERGER.

Witnesses PAULA Bar, FLORENCE M. Losse'rn.

